Wireless signaling.



R. A. FESSENDEN.

WIRELESS SIGNALNG. APPLIUATION FILED APR. 5, 1307. I 19022954@ lPatented Apr. 9, 1912.

QV@ kunnen REGINALD a. rnssnnnnn, 'or BRANT noon, MASSACHUSETTS, assren'on To NArIoNAL I t ELECTRIC srenanrn'e coMrANY, or PITTSBURGH', PENNSYLVANILA conforte- TICN or new masas.

WIRELESS SIGNALING.-

Specification of Letters Patent. Application led April 5, 1907. Serial Heit-16,528.

' Patented Apr.9, 1915.2.

To all whom t may concern Be it known that l, Ramiseto A. Fassun- DEN, a citizen of the United States, residing at Brant Rock, in the State of Massachusetts, have invented certain new and useful Improvements in ,lireless' Signaling, of

which the following is a specifica-tion.

My invention relates to simultaneo-us sending and receiving of signals andmore i@ particularly to the simultaneous transmission and receipt oli telephonie messages, and

to multiplex telegraphy and telephony generally. lts primary object is the simultaneous transmission and receipt of one or i5 more telegraphic or telephonie messagesv at a wireless station, and also the transmission ci messages to and from a wireless station -over wire lines.

ln the accompanying drawing forming a part of this specification the figure shows in diagram a. suitable arrangementfor carrying out the invention.

In' the drawing 1 and 2 at the bottom of the diagram represent wire lines leading to a telegraph oiiice or a telephone central, 3 and 4 represent the magnet coils of telephone relays, and 5 and 6 the transmitter buttons or their equivalents.

7, 8, v9, represent the primaries of the 30 telephone induction coils and 11, 12, 13, 14,

the corresponding secondaries.

is a resistance to balance resistance of the telephone line 1, 2.

The primaries and secondaries are so wound and-connected that signals or speech impulses transmitted by means of the transmitter button 6 are balanced as regards their eiect on the magnet coil 3.

16 is a local battery, 17 (at the top) is a source of voltage, preferably al continuous current dynamo, or otherwise mayk be storage bat-teries, 18 is an adjustable resistance, 19 is a discharge gap, 20, 23, 24, 25, 26, 27, 28, 29 are variable capacities; 21, 22, 30, 31 are the primaries of the transformers whose secondaries are 32j, 33, 34, 35. 37 is an inductance which may be variable, 38 a resista-nce, 39 an inductance preferably variable ancl 40 an antenna grounded at ,41, and 42 is a variable capacity. rl`hese primaries and secondaries are so wound and connected, and the various inductances and capacities so adjusted empirically that on sendin by the sending-key 44 (or when this is ort ,55 circuited by the switch 45, then on talking or telegraphing by the line4 1, 2) it will not affect the receiver 46. rlyhis receiver 46 is connected in with whatis Well known in the art as an interference preventer as shown here, or as illustrated in my former patents such as No. 918,307, of April 13th, 1909, `ig. 4); 47, 48 being the primaries and 49 a'nd .5()Y the corresponding secondaries, 51 a capacity and 52 a potentiometer.

, The condenser 26, inductance 37 and resistance 38 form what may be called a. phantom antenna, e., they appear to absorb energy to the`l same extent and to the same amount as the antenna 40 and its connections to ground, and to balance it. rlhis arrangement therefore is believed to be somewhat similar in principle 'tot-he balancing arrangement shown at the lower part of the figure in connection with the wire lines and above described.

ln operation, on sending a telegraphic or telephonie current through the line 1, 2. the sw1tch 45 being closed, the telephonie or telegraphic currents actuate kthe relay 3, 5 and cause signals to be sentfout from the @0 antenna 40 without aiieecting the receiver 46, or onlyaiecting it to a very slight extent. @n the other hand electric waves simultaneously received on the antenna 40 actuate the receiver 46 and by the means ot 85 the telephonie relay 4, 6, are transmitted baci: on the line, 1, 2. Similarly it' the switch 45 be open, asimilar result is obtained on telegraphing with the key 44, in which case the operator may listen `to signals received or sent by means of the telephone receiver 53.

v/'here it is desired to simultaneously transmit and receive a number of messages at the same time, dierent antennae may be used suspended from the same tower or the same antenna ma be used by duplicating the apparatus as s own to the right ot ligure, corresponding pieces of apparatus being there indicatedt by corresponding iigures with the prime mark added. rllhe sending and 'receiving circuits on the right lor the will -iigure are tuned to a dierent frequency from that or the circuits on the left-hand side.

By means ofthe apparatus and operation described it` is possible to simultaneously send and receive one or more telephonie or tel-egraphic messages,..l either directly trom the wireless. station, or from local stat-ions nel connected byf-wires with the wireless station.

I do not limit myself to the specific arrangementsherein vset forth, as there are -many alternative arrangements which may be used which are fully equivalent or which tlzpnie under the broad invention as claimed.

ut v

Having thus described my invention and illustrated its use, what I claim herein as new and desire to secure by Letters Patent, is the following:

1. In the art of simultaneous transmission and receipt of wireless signals, the method of neutralizing the eiect of the local sending circuit at a station,l on a local receiving circuit, which consists .in operatively 'con necting a balancing circuit, and the local sending source to the antennae, adjusting said C11-cuits so asv to malntaln a difference Aof approximately zero potential between described'.

3. In wireless telegraph apparatus, means for receiving signals, without interference .from signals being simultaneously sent out at the same station, comprisingan antenna 'circuiti andl a second circuit operatively connected thereto and having its electrical constants arrangedyproportionately to those of the antenna circuit, saidv two circuits being so adjusted as to create two points in the sending circuit located on opposite sides of the connection to the receiving circuitfwith zero potential between them so far as concernsthe effect of the impulses being sent.

4. Wireless telegraph apparatus, comprising an antenna circuit and a second circuit operatively connected thereto and having its electrical constants arranged proportionately to those of the antenna circuit, and means to adjust said circuit so as to create two points in the sending circuit located on opposite sides ofthe connection to the receiving circuit with zero potential between them so far as concerns the effect of the impulses being sent, a telephone relay transmitter in operative relation to the source of the transmitted impulses, a line wire and a receiving electromagnetic instrument in operative relation to the line 4wire.

5. In wireless telegraphy, means for simultaneously sending and receiving impulses and preventing their disturbing each other, comprising devices for balancing the receiving circuit against impulses sent out on the same antenna, the receiving circuit being connected between two points on the sending circuit which are maintained at zero potential with respect to the impulses sent out, substantially as described.

6. In wirelesstelegraphy, means for preventing mutual disturbances in simulta neously sending and receiving, by dividing the impulses which would a'ect Athe receiver, so as toj produce opposing effects on the receiving circuit, which comprises a supplementary circuit containing capacity, linductance and resistance proportional to that ofl the antenna and a receiving circuit lconnected across the points of junction thereof with't-he antenna whereby to balance the effects on the receivers,substantially as described.

In testimony whereof I have hereunto signed my name in the presence of the subscribing witnesses. j f

REGINALD A. FESSENDEN.

Witnesses:

1I-Essie E. BENT,

AnELEiNn WOLENER. 

